FairValue

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Mads

Roerslev

RBDenmark · Southampton FC

№ 391005Established €4.3M −0.08

Player dossierPremier League

MadsRoerslev

RBRight-BackDefender

Club
Southampton FC
League
Premier League
Nationality
Denmark
Age
26
Height
184 cm
Foot
Right
Valued
28 May 2026

Reading the valuation

The market values Roerslev at €4M. Model A, which never saw Roerslev during training, estimates €4.3M: the market value is 7% below that estimate.

That is a factor of ×1.08. Model A's typical held-out miss is ×1.50 either way, so this gap is within its usual error.

Without league and club, Model B estimates €959k, further from the market. Model B is usually further off (typical miss ×2.07): league and club explain much of how the market prices players.

A gap describes the model's arithmetic for this player's inputs, not what the player is worth.

▼ −0.08A €4.3M▲ +1.43B €959k
Pitch length is a log value scale fitted to this player's figures. ● observed · ◇ Model A · dashed ◇ Model B · each arc is a residual, log(observed) − log(estimate).
Apps
28
Minutes
1,573
Goals
0
Assists
3
Started
15/28
Min / app
56
Cards
2Y 0R

Club matches, two years to the valuation date

The Valuation Journey

What moves Model A

Asking the prediction API to explain Model A for Roerslev…

SHAP describes the model's arithmetic for this player's inputs, not what causes market value. Model B can be explained only by the live service; Model A also has a published explanation for the research players.

Model A vs Model B against the observed €4M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €4MModel A €4.3M

Asking the prediction API…

Held-out estimates come from cross-validation, with this player outside the training data: the honest comparison. Served models were refitted on every player, this one included, so they sit closer to the market. Shaded band: Model A's typical miss (×1.50 either way).

Player traitspercentiles vs 2,065 defenders

Mads Roerslev's percentiles among defenders: Goals per 90 18th, Assists per 90 92nd, Minutes, two years 24th, Starts 10th, Minutes, last 365 days 3rd, European club minutes 30th18thGoals92ndAssists24thMinutes10thStarts3rdRecent30thEurope

Dashed ring: the defender median (50th percentile)

Assists per 90

Club assists per 90 minutes in the same window.

0.17 this player0.04 defender median92nd percentile

0.00peer deciles · median line · this player ●0.58

No passing, progression or defensive actions exist in the dataset, so no trait claims to measure them.

Valuation history every Transfermarkt valuation on record

First valuation
€150k
Jun 2017
Peak
€12M
Dec 2024
Model target
€4M
May 2026
Valuations
22
5 club changes
May 2026€4MSouthampton FCValuation the model is trained to reproduce

May 2026: €4M, Southampton FC. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2017-06-21€150kFC Copenhagen U19
2017-12-18€150kFC Copenhagen
2018-06-02€200kFC Copenhagen
2018-12-21€300kFC Copenhagen
2019-06-08€250kVendsyssel FF
2020-02-27€500kBrentford FC
2020-04-08€450kBrentford FC
2020-10-15€450kBrentford FC
2021-03-10€500kBrentford FC
2021-06-30€1.5MBrentford FC
2021-12-23€1.5MBrentford FC
2022-06-15€2.5MBrentford FC
2022-11-03€2.2MBrentford FC
2023-06-20€6MBrentford FC
2023-12-19€8MBrentford FC
2024-05-27€10MBrentford FC
2024-12-16€12MBrentford FC
2025-03-27€8MVfL Wolfsburg
2025-06-05€6MVfL Wolfsburg
2025-12-03€6MSouthampton FC
2026-03-03€5MSouthampton FC
2026-05-28€4MSouthampton FC

Audit context group-level, not about this player

Audit group
UEFA
Population gap, Model A
+0.093 95% CI +0.063 to +0.124
This player, market vs held-out A
−0.077

The group comes from first-listed citizenship and is never a model input. Across the population, non-UEFA players' market values sit about 10% above Model A's held-out estimates, relative to UEFA players in the same leagues. One player's residual says nothing about that pattern (typical miss ×1.50), and none of it is evidence of discrimination: the target may itself be biased. Open the Fairness Audit

In context observed value among comparable players in this build

All players in the Terminal →

Premier League555 players · median €18M

Valued above 16% of the 555 Premier League players.

€150k€1M€7.5M€50M€4MSee them in the Explorer →

Defenders, all leagues2,065 players · median €2M

Valued above 65% of the 2,065 defenders.

€20k€200k€2M€20M€4MSee them in the Explorer →

Where Roerslev appears

Watchlists and the comparison tray are kept in this browser only.

Near this valuation closest observed values: same league, then same position

Counts and ranks of observed Transfermarkt values only; model errors are never ranked here. Full player export: Every player in the modelling population (D-011).